CooperSurgical Mobius Retractor. Box of 5 (Different Sizes) Sizes: CooperSurgical 900-508 Mini Retractor, 8 cm I.D. ring, for incisions to 6 cm.CooperSurgical 900-500 Small 11cm I.D. ring, for incisions to 9 cm.CooperSurgical 900-515 Medium 15 cm I.D. ring, for incisions to 14 cm.CooperSurgical 900-517 Med-Large 17 cm I.D. ring, for incisions to 15 cm.CooperSurgical 900-520 Large 22 cm I.D. ring, for incisions to 17 cm. This Mobius provides maximum exposure and wound protection while keeping...